Merge #168

168: Scheduled weekly dependency update for week 47 r=mithrandi a=pyup-bot




## Updates
Here's a list of all the updates bundled in this pull request. I've added some links to make it easier for you to find all the information you need.
<table align="center">

<tr>
<td><b>hypothesis</b></td>
<td align="center">3.37.0</td>
<td align="center">&raquo;</td>
<td align="center">3.38.0</td>
<td>
     <a href="https://pypi.python.org/pypi/hypothesis">PyPI</a> | <a href="https://pyup.io/changelogs/hypothesis/">Changelog</a> | <a href="https://github.com/HypothesisWorks/hypothesis/issues">Repo</a> 

</td>

</tr>
</table>



## Changelogs


### hypothesis 3.37.0 -> 3.38.0

>### 3.38.0

>-------------------

>This release overhauls :doc:`the health check system &lt;healthchecks&gt;`
>in a variety of small ways.
>It adds no new features, but is nevertheless a minor release because it changes
>which tests are likely to fail health checks.

>The most noticeable effect is that some tests that used to fail health checks
>will now pass, and some that used to pass will fail. These should all be
>improvements in accuracy. In particular:

>* New failures will usually be because they are now taking into account things
>  like use of :func:`~hypothesis.strategies.data` and
>  :func:`~hypothesis.assume` inside the test body.
>* New failures *may* also be because for some classes of example the way data
>  generation performance was measured was artificially faster than real data
>  generation (for most examples that are hitting performance health checks the
>  opposite should be the case).
>* Tests that used to fail health checks and now pass do so because the health
>  check system used to run in a way that was subtly different than the main
>  Hypothesis data generation and lacked some of its support for e.g. large
>  examples.

>If your data generation is especially slow, you may also see your tests get
>somewhat faster, as there is no longer a separate health check phase. This will
>be particularly noticeable when rerunning test failures.

>This work was funded by `Smarkets &lt;https://smarkets.com/&gt;`_.

>-------------------









That's it for now!

Happy merging! 🤖

requirements.txt

@@ -19,7 +19,7 @@ extras==1.0.0
 fixtures==3.0.0
 fusion-util==1.3.0
 hyperlink==17.3.1
-hypothesis==3.37.0
+hypothesis==3.38.0
 idna==2.6
 incremental==17.5.0
 ipaddress==1.0.18